The top Democrats on congressional banking committees called on the Federal Reserve to reconsider its decision to approve Capital One Financial Corp.’s purchase of Discover Financial Services, saying it would inflict “serious harm” on consumers and the banking system. The decision sounds like the Fed “had predetermined it was going to approve the transaction and either ignored relevant facts or explained them away with baseless assertions copied and pasted from Capital One’s application,” Senator Elizabeth Warren and Representative Maxine Waters said in a letter sent to the Fed. “Treating the transaction as a traditional bank merger was deeply misguided,” the lawmakers wrote. “These are not two traditional banks — they are card giants.” Warren and Waters emphasized the Fed’s review failed to appropriately assess the competitive effects on the credit-card market and didn’t take into account the views of the Consumer Financial Protection Bureau and the Federal Deposit Insurance Corp. The Fed said in an order last month that it consulted with other regulatory agencies including the FDIC and CFPB. Capital One said the deal’s approval follows “an exhaustive, fact-based 14-month examination where legal and regulatory experts examined the deal’s competitive impact, financial stability considerations, community needs, and all other relevant factors.”