David is a long-time member of the Lone Star Chapter Sierra Club executive committee where he has worked with other environmental leaders throughout Texas on statewide and local issues for almost a decade. David also has served as a liaison to the national office of Sierra Club for the Lone Star Chapter.

David is a former Civil Prosecutor for the U.S. Federal Trade Commission in Dallas and previously was an adjunct professor of business law in the Graduate School of Management at the University of Dallas. 

His key activities as political chair of the Dallas Sierra Club include organizing voter information initiatives to inform voters on environmental issues and positions of candidates during elections. David also is the political chair for the Lone Star Chapter. He works with statewide Sierra leaders to interview candidates about their environmental ideals, assess their overall green position, and then makes Sierra Club voter recommendations with Sierra groups statewide. He also raises funds to support environmentally friendly politicians at the local, state, and national level. These contributions help defray election expenses for green candidates.

His environmental activism began in 1997, when working with his now wife Rita Beving, David helped raise more than $100,000 against a permit for the expansion of burning hazardous waste by TXI in Midlothian. During that legal case with Downwinders at Risk and others, David employed Brookhaven graduate students he taught into executing a health study with Galveston toxicologist Marvin Legator to show a relationship between the toxic emissions from this facility and health effects in the area.

David also has worked with groups and activists statewide during Dallas Mayor Miller’s tenure to help defeat 12 proposed coal-fired power plants that TXU wanted to build. He has worked on various national Sierra Club conservation campaigns over the years.

In 2016, David assisted with the Dallas Sierra Club's effort to assist the Los Altos Neighborhood Association Homeowner's Association of West Dallas in preventing new cement kilns from being located next to homes and schools. Originally the local Dallas City Council Member ignored pleas by her constituents to keep those plants out of neighborhoods, so they turned to the Sierra Club for help. David worked with the local community and rallied support of other City Council Members and different environmental organizations to convince the local council person to withdraw her support for the plants.

Recently in March 2018, David co-led Dallas Sierra Club activities to oppose a new concrete batch plant proposed for the Joppa community in South Dallas that would significantly impact air quality because of high levels of particulate emissions. He canvassed the Joppa neighborhood door-to-door with Councilman Kevin Felder and others to obtain signatures on a petition to oppose the plants. He persuaded Neil Carman, the Texas state expert on particle contamination, to speak about health risks at public meetings. He then helped educate other council members about the health risks associated with high particulate levels, and spoke against the proposal in the Dallas City Council Meeting. These activities were critical to defeating the proposed zoning change and prevent further deterioration of Joppa air quality.

Presently, David serves as the Chair of the Sustainability Committee for the city of Farmers Branch. With the help of those serving on that committee, Farmers Branch is now establishing the beginning of a water conservation program with the help of Clean Water Fund. Within the past three years, David, along with other Sustainability committee members, also secured the necessary Council votes to establish the recycling program for the City of Farmers Branch.

David also serves on the Sustainability Committee for Dallas County Community College District, working with faculty and staff to establish greener programs on campus and bring educational forums to students.

David continues to work with a number of organizations in coalition to achieve environmental goals. He always is reaching out to new communities and to other environmental organizations in North Texas and beyond. Some of the local organizations he collaborates with on environmental work include Public Citizen, Clean Water Fund, Texas Campaign for the Environment, Citizens Climate Lobby, and others.

David is active in leadership roles for numerous governmental organizations, including the Dallas Bar Association, where he is the Chair of the Community Education subcommittee, a member and former Chair of the Community Involvement Committee, and a member of the Judiciary Committee.

He is also a member of the American Constitution Society for Law and Policy, the Farmers Branch Chamber of Commerce and Governance Committee, President of the Dallas-Saratov Russia Sister City Committee, President of the Dallas Democratic Forum, a board member in the DFW International Community Alliance, and a former member of the World Affairs Council of DFW. He also is active in the Democratic Party of Dallas and is the SDEC representative for District 16.

As an instructor of both political science and criminal justice at Brookhaven College since 1995, David teaches the fundamentals of government and Texas law as it applies to policing, crime, and criminal punishment. He also has established a criminal justice club at Brookhaven where they take an annual trip to London, the city where policing was born, visiting top law enforcement groups in the UK.

For many years, David also served on the Dallas United Nations Association board, which fostered support for the UN and its efforts worldwide.

David also has been a pivotal person in Methodist work with his church. For many years, he led a mission group to Saratov, Russia, connecting medical experts and medical supplies with hospitals, securing clothing for Russian orphans, and helped establish a Methodist church in Saratov. He also worked with the city of Dallas to establish Saratov as a sister city.