In a muddy global banking sector, Deutsche Bank (NYSE:DB) shines like a diamond.

In the first quarter of this year, the German investment bank reported net earnings of 1.2 billion euros ($1.5 billion), or 1.92 euros per diluted share, versus a loss of 141 million euros, or 27 cents per diluted share, in the same quarter last year.

By far the bulk of that was in windfall profits derived from debt trading. After Deutsche reported, critics were quick to sharpen knives over what they claimed was a hard-to-replicate, one-off fluke event. Some of the same naysayers then pooh-poohed the decision to let veteran chief executive Josef Ackermann stay on until 2013, citing an unwillingness on the bank’s part to move on.

But in a world where liquidity is hardly flowing like tap water, even one-time windfall profits can be a huge competitive advantage when it comes to expanding operations.

What’s more, those profits weren’t derived from dubious accounting methodologies the way Goldman Sachs (NYSE:GS), JPMorgan Chase (NYSE:JPM), and Citigroup (NYSE:C) seemingly generated their magical first-quarter earnings. They were cold cash.

And it’s hard to see how further management stability is a bad thing when Deutsche’s competitors are suffering from an exodus of top management. When contrasted with Bank of America’s (NYSE:BAC) wobbly indecision over whether to keep its former chairman and current CEO, Ken Lewis, for example, holding onto the man at the helm amid a credit crisis looks impressive.  

While Ackermann was talking about “attack[ing] market share” at the end of the quarter, other banks were still trying to figure out how to pay back government TARP funds. That makes Deutsche about the only big bank aiming its sights higher right now.

Some of this is due to Deutsche’s clever market positioning. While it’s a European bank, it has an investment banking model similar to those in the United States. That unique structure gives it an edge on the global playing field.

Deutsche’s shares have risen about 65% this year, more than those of its competitors (except Goldman Sachs and Morgan Stanley (NYSE:MS)). You can bet on that being another negative among the anti-Deutsche crowd in coming weeks, as investors continue to look for increasingly outsized returns on what’s left of beaten-down stock prices.

My advice is not to get suckered into the carping. Deutsche may not be the cheapest or the most flashy financial play around, but it’s hard to find another firm in the banking space that looks more solid right now.