While reading Spencer S. Hsu’s superb but disturbing April 17 front-page article, “Defendants left unaware of flaws found in cases,” I was reminded of the importance of investigative journalism, inspectors general, public defenders, public-interest groups and the Freedom of Information Act. Without the supporting roles of each, we might not be educated and enlightened to the degree we now are as a result of Mr. Hsu’s work about law enforcement’s curious treatment of forensic evidence in cases where lives can hang in the balance.

But that is not nearly enough. Policymakers need to investigate and correct any systemic problems with respect to the collection, interpretation and use of forensic evidence by the Justice Department and FBI. Anything less would be unforgivable in a democratic nation that prides itself on the enduring, nonnegotiable principles of  liberty, equality and justice for all.

Jeffrey S. Silva, Bethesda

The Post series documenting problems with forensic analysis at the FBI’s crime lab, and the efforts of officials to conceal the findings, has certainly been eye-opening. One can understand mistakes; one can even understand ignoring sound scientific principles to establish meaningful procedures and protocols. One is hard-pressed, however, to understand why such things should be deliberately concealed from defendants, except for the notion that the people involved were more concerned with protecting agencies and prosecutors than in obtaining impartial justice.

Orin Hollander, Jamison, Pa.

Regarding the April 18 front-page article “Reviewed lab work held close to the vest”:

I would add that the forensic process lacked independence. I don’t think that controls and higher standards are adequate to prevent FBI managers from failing again, as the article noted that they have in the past, “to respond to warnings about the scientific integrity and competence of agents.” The pressure to prosecute and convict is too great.

I think what might be necessary is a separation of the crime lab and all forensics from the control of the FBI. They should instead be placed under the control of an independent authority.

Paul Heishman, Vienna