After the bombing, Davis became the face of the response. Almost every legislator who asked questions in Thursday's hearing thanked him for his service.
Davis used that high-profile response as proof that reforms to the nation's video surveillance are needed, writing that in order to catch the bombers, law enforcement officials rely "almost exclusively on the support of our business partners to provide critical video surveillance along the finish line."
"I strongly support the enhanced ability to monitor public places," he wrote. "This monitoring, which been upheld by the United States Supreme Court, violates no constitutionally protected rights but gives police the ability to investigate and effectively prosecute. Images from cameras do not lie. They do not forget. They can be viewed by a jury as evidence of what occurred."
In the hunt for the Tsarnaev brothers, surveillance video proved crucial. Investigators solicited video from many of the business around the marathon route and used it to locate the bombing suspects. On April 18, the FBI released surveillance-camera pictures of the brothers.
Although Thursday's meeting is the first congressional hearing on the Boston bombing, it certainly will not be the last. Legislators in both the Senate and the House have expressed an interest in hosting experts to discuss what to learn from the terrorist attack.
The Boston bombing saga began after the two bombs went off at the Boston Marathon finish line on Boylston Street on April 15. Hundreds of Boston law enforcement officers then began a gripping week long search for those who carried out the terrorist attack.
Late at night on April 18, Massachusetts Institute of Technology police officer Sean Collier was shot and killed on campus, allegedly by the bombing suspects. In the early morning of April 19, the suspects allegedly hijacked a car in Cambridge and led police on a high speed chase through Cambridge and Watertown, two Boston suburbs. In a shootout during the chase, the older Tsarnaev brother was wounded by gunfire. He later died at a hospital.
Throughout much of that day, hundreds of law enforcement officers went door-to-door on 20 streets in Watertown, looking for Dzhokhar Tsarnaev. Residents around Boston were asked by authorities to stay inside as the hunt continues for the suspect.
In the early evening of April 19, David Henneberry discovered Tsarnaev, wounded, hiding in his boat. He alerted police, and after a tense standoff, police took him into custody.
Dzhokhar Tsarnaev, who was in serious condition at the time of his capture, is now stable and charged with one count of using and conspiring to use a weapon of mass destruction resulting in death and one count of malicious destruction of property by means of an explosive device resulting in death.
In addition to Tsarnaev, three 19-year-olds -- Azamat Tazhayakov, Dias Kadyrbayev, and Robel Phillipos -- were arrested in connection with the bombings. The three are accused of helping Tsarnaev after the bombing by taking items from his dorm room in an effort to keep them from investigators.